Method of fabricating capacitive touch panel

ABSTRACT

The present disclosure relates to a method of fabricating a capacitive touch pane where a plurality of groups of first conductive patterns are formed along a first direction, a plurality of groups of second conductive patterns are formed along a second direction, and a plurality of connection components are formed on a substrate. Each first conductive pattern is electrically connected to another adjacent first conductive pattern in the same group by each connection component and each group of the second conductive patterns is interlaced with and insulated from each group of the first conductive patterns. Next, a plurality of curved insulation mounds are formed to cover the first connection components. Then, a plurality of bridge components are formed to electrically connect each second conductive pattern with another adjacent second conductive pattern in the same group.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of co-pending U.S.application Ser. No. 14/023,636, which is a divisional application ofU.S. Pat. No. 8,557,508, filed on Mar. 9, 2010, which claims thepriority to China Patent Application No. 200910301532.8 filed in theChina Patent Office on Apr. 13, 2009, which is herein incorporated byreference in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a method of fabricating a touch panel,especially to a method of fabricating a touch panel that is simple andhas high accuracy.

2. Description of Related Art

In today's markets, which offer a variety of consumer electronicsproducts, the touch panel has been increasingly used in personal digitalassistants (PDA), mobile phones, notebooks and other portable electronicproducts, as well as personal computers and digital home appliancesystems as a communication interface between users and the electronicdevices. When using the touch panel, users can directly operate theelectronic devices and make commands through screen objects displayed onthe panel, providing a more user-friendly operation interface. Inaddition, electronic products are currently designed to be light, thin,short and small, and it is therefore desirable to economize the spacededicated to some traditional input devices, such as buttons, keyboards,and mice, in product design. Display devices with touch panels are acurrent trend, and are one of the key components of all kinds ofelectronic products.

Conventional touch panels can be categorized into capacitive, resistiveor surface wave touch panels in accordance with their detectionprinciple, each having different advantages and disadvantages, anddifferent application fields. The resistive touch panel includes anupper transparent conductive film and a lower transparent conductivefilm that are superimposed to each other. When the user presses thetouch panel, strength of the depression makes the upper electrodeconnect to the lower electrode, and the touch point position can becalculated through the measurement of the voltage change. The surfacewave touch screen has a wave source, usually infrared or ultrasound, onone side of the X-axis and Y-axis of the panel and has a receiver on theother side. When a user touches the panel, the waveform is interferedwith, and the interference graph can be captured by the receiver, suchthat the position can be calculated. The capacitive touch screenprovides a uniform electric field at the four corners of the panel, andthe touch position can be measured by detecting changes of capacitanceof the panel.

Due to the advantages of being dust-proof, and having high temperatureresistance and multi-touch capability, conventional capacitive touchpanels are widely used in portable electronic products. However, aconventional capacitive touch panel usually includes a stack of at leastfive films, making it hard to achieve a high light transmission ratio,which may result in low display quality. And, because of its largevolume and heavy weight, conventional capacitive touch panels are alsodifficult to integrate into current electronic devices, which aredesigned to be thin and light. Moreover, the multilayer stackingstructure requires a more cumbersome fabrication process, especiallywhen the sensing conductive films are located on both sides of atransparent substrate, rendering the manufacturing process difficult toupgrade.

SUMMARY

An embodiment of the disclosure provides a method of fabricating acapacitive touch panel. The method comprises the following steps.Firstly, a substrate is provided. Then, a plurality groups of firstconductive patterns arranged in a first direction, a plurality groups ofsecond conductive patterns arranged in a second direction, and aplurality of connection components are formed on the substrate. Eachfirst conductive pattern is electrically connected to another adjacentfirst conductive pattern in the same group by each connection component,and each group of the second conductive patterns is interlaced with andinsulated from each group of the first conductive patterns. Then, aplurality of curved insulation mounds are formed on the substrate. Eachinsulation mound covers at least a portion of each connection component.Lastly, a plurality of bridge components are formed on the insulationmounds. Each second conductive pattern is electrically connected toanother adjacent second conductive pattern in the same group by eachbridge component.

Another embodiment of the disclosure provides a method of fabricating acapacitive touch panel. The method comprises the following steps.Firstly, a substrate is provided. Then, a plurality of groups of firstconductive patterns arranged in a first direction and a plurality ofconnection components are formed on the substrate. Each first conductivepattern is electrically connected to another adjacent first conductivepattern in the same group by each connection component. Then, aplurality of curved insulation mounds are formed on the substrate. Eachinsulation mound covers at least a portion of each connection component.Lastly, a plurality groups of second conductive patterns arranged in asecond direction and a plurality of bridge components are formed on thesubstrate. Each group of the second conductive patterns is interlacedwith and insulated from each group of the first conductive patterns, andeach bridge component is formed on each of the insulation mounds suchthat each second conductive pattern is electrically connected to anotheradjacent second conductive pattern in the same group by each bridgecomponent.

Another embodiment of the disclosure provides a method of fabricating acapacitive touch panel. The method comprises the following steps.Firstly, a substrate is provided. Then, a plurality of bridge componentsare formed on the substrate. Next, a plurality of curved insulationmounds are formed on the substrate. Each insulation mound covers eachbridge component and exposes a portion of each bridge component. Lastly,a plurality of groups of first conductive patterns arrange in a firstdirection, a plurality of groups of second conductive patterns arrangedin a second direction, and a plurality of connection components areformed on the substrate. Each first conductive pattern is electricallyconnected to another adjacent first conductive pattern in the same groupby each connection component, each group of the second conductivepatterns is interlaced with and insulated from each group of the firstconductive patterns, and each second conductive pattern is electricallyconnected to another adjacent second conductive pattern in the samegroup by each bridge component below each insulation mound.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objectives of the present disclosure will no doubtbecome obvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various FIGS. and drawings.

FIG. 1 illustrates a schematic diagram of a first embodiment of a methodof fabricating a capacitive touch panel in the present disclosure.

FIG. 2 illustrates a left part L showing an enlarged schematic diagramof the circle A in FIG. 1, and a right part R showing a cross sectionaldiagram along line BB′ in circle A.

FIG. 3 illustrates a schematic diagram of a curved insulation moundafter a baking process.

FIG. 4 illustrates a schematic diagram of forming a patterned mask layeron a substrate according to the first embodiment in the presentdisclosure.

FIG. 5 illustrates a schematic diagram of forming a conductive film onthe substrate according to the first embodiment in the presentdisclosure.

FIG. 6 illustrates a schematic diagram of removing the patterned masklayer in FIG. 5.

FIG. 7 illustrates a schematic diagram showing a plurality of groups(rows) of the first conductive patterns and a plurality of groups(columns) of the second conductive patterns arranged in differentdirections formed on the same side of the substrate according to thefirst embodiment in the present disclosure.

FIG. 8 illustrates a schematic diagram of forming a metal layer on thesubstrate according to the first embodiment in the present disclosure.

FIG. 9 illustrates a schematic diagram of first conductive patterns andconnection components according to a second embodiment of a method offabricating a capacitive touch panel in the present disclosure.

FIG. 10 illustrates an enlarged schematic diagram of the circle C inFIG. 9.

FIG. 11 illustrates a schematic diagram showing a plurality of groups(rows) of the first conductive patterns and a plurality of groups(columns) of the second conductive patterns arranged in differentdirections formed on the same side of the substrate according to thesecond embodiment in the present disclosure.

FIG. 12 illustrates a schematic diagram of bridge components and curvedinsulation mounds according to a third embodiment of a method offabricating a capacitive touch panel in the present disclosure.

FIG. 13 illustrates a schematic diagram of forming a plurality of groupsof first conductive patterns, a plurality of groups of second conductivepatterns, and a plurality of connection components according to thethird embodiment in the present disclosure.

FIG. 14 illustrates a schematic diagram showing a plurality of groups(rows) of the first conductive patterns and a plurality of groups(columns) of the second conductive patterns arranged in differentdirections formed on the same side of the substrate according to thethird embodiment in the present disclosure.

DETAILED DESCRIPTION

FIGS. 1-8, illustrate schematic diagrams of a first embodiment of amethod of fabricating a capacitive touch panel in the presentdisclosure. Referring to FIG. 1, a substrate 301 is provided at first.The substrate 301 may include organic materials or inorganic materials,such as glass, quartz, plastics, resins, acrylic or other suitabletransparent materials. Then, a transparent conductive layer (not shown)is formed on the substrate 301. The transparent conductive layer may bea single layer or a multi layer, and it may include a variety ofconventional transparent conductive materials, such as indium-tin-oxide(ITO), indium-zinc-oxide (IZO), zinc-oxide-aluminum (AZO),zinc-oxide-gallium (GZO) or magnesium-indium-oxide (MIO).

Then as shown in FIG. 1, a photo-etching-process (PEP) is provided topattern the transparent conductive layer to form a plurality of groupsof first conductive patterns 303, a plurality of groups of secondconductive patterns 307, and a plurality of connection components 305 onthe surface of the substrate 301. Among them, each group of the firstconductive patterns 303 is arranged along a first direction 309 and eachgroup of the second conductive patterns 307 is arranged along a seconddirection 311. Each first conductive pattern 303 is electricallyconnected to another adjacent first conductive pattern 303 in the samegroup by each connection component 305 as a monolithic art. Each groupof the second conductive patterns 307 and each group of the firstconductive patterns 305 are interlaced with and insulated from eachother.

As shown in FIG. 1, in the embodiment of the present disclosure, thefirst direction 309 and the second direction 311 are perpendicular.However, the arrangement can be ordered to change the distribution ofthe conductive patterns, so the first direction 309 and the seconddirection 311 intersect at a non-perpendicular angle. It should beunderstood by one of ordinary skill in the art that if the substrate 301were rotated in a counter-clockwise manner or in a clockwise manner, forexample, to make each group of the first conductive patterns 303 bearranged along the second direction 311, and each group of the secondconductive patterns 307 be arranged along the first direction 309, suchembodiments would represent equivalent changes and modifications of thepresent disclosure and should be covered by the scope of the presentdisclosure.

Subsequently, a plurality of wires 308 are formed on the edge ofsubstrate 301. One end of each wire 308 is connected to each group (row)of the first conductive patterns 303 or each group (column) of thesecond conductive patterns 307, and the other end of each wire 308stretches to the edge of the substrate 301 to serve as an outer panelcontrol circuit in the subsequent steps. The step of forming the wires308 may also include forming at least one alignment mark 310 on the edgeof the substrate 301. The alignment mark 310 can help to calibrate theposition in the follow-up manufacturing processes. The step of formingthe wires 308 and the alignment mark 310 are not limited to beingperformed after the formation of the first conductive patterns 303, thesecond conductive patterns 307, and the connection components 305. Thewires 308 and the alignment mark 310 may also be formed before theformation of the first conductive patterns 303, the second conductivepatterns 307, and the connection components 305, or the wires 308, thealignment mark 310, the first conductive patterns 303, the secondconductive patterns 307, and the connection components 305 may also beformed simultaneously. The step may also be placed between other stepswhen not affecting the processes.

FIG. 2 shows a left part L showing an enlarged schematic diagram of thecircle A in FIG. 1, and a right part R showing a cross sectional diagramalong line BB′ in circle A, so as to provide more detailed illustrationof the manufacturing process between each component in the embodiment ofthe present disclosure. As shown in FIG. 2, a photoresist layer or otherphotosensitive insulation layer (not shown) is formed on the substrate301. After the position calibration by the alignment mark 310, alithography process is performed on the photoresist layer, for example,an exposure process and a development process, so as to form a pluralityof photoresist patterns 313. Each photoresist pattern 313 covers thecorresponding connection components 305. In one embodiment, eachphotoresist pattern 313 covers at least each corresponding connectioncomponent 305 and a portion of each adjacent first conductive pattern303, as shown in FIG. 2.

In FIG. 3, a baking process (not shown) is performed. The temperature ofthe baking process is between about 200 to 300 degrees Celsius, forexample 220 degrees Celsius, for about one hour. During the bakingprocess, a cohesion phenomenon occurs on each photoresist pattern 313,thereby forming a curved insulation mound 315 respectively.

It should be understood that compared to a conventional photoresistlayer, which will be removed after the photo-etching-process, theinsulation mound 315 in the embodiment of the present disclosure willnot be removed. The insulation mound 315 is formed directly from thephotoresist pattern 313 after the baking process. Since the insulationmound 315 will not be removed, in addition to having thephotosensitivity property, the persistence and stability of the selectedmaterials of the photoresist pattern 313 should be considered as well,so as to provide solidity and a supporting function of the insulationmound.

In addition to the aforementioned process to form the insulation mound315 directly from the photoresist layer 315, the insulation mound 315can also be fabricated by using a photo-etching process. For example, aninsulation layer is formed on the substrate at first and then theinsulation layer is etched to form a plurality of insulation patternsthat cover a portion of each connection component respectively. Then, athermal reflow process is provided to make each insulation patternbecome a curved insulation mound 315. Alternatively, the insulationmound 315 in the embodiment of the present disclosure can also be formedby an inkjet printing process.

After forming the insulation mound 315, please refer to FIG. 4. Aphotoresist layer 317 is deposited on the substrate 301 comprehensively,and the photoresist layer 317 includes a lift-off photoresist material.Then, a soft baking process is performed. By the position calibration ofthe alignment marks 310, an exposure process is then performed.Substantially, a baking process 319 is performed on the substrate 301.Particularly, this baking process 319 may bake the bottom of thesubstrate 301, that is, the bottom of the photoresist layer 317 is bakedby the heat conduction from the substrate 301 in the baking process. Thetemperature of the baking process is between 80 to 120 degrees Celsius,for example 100 degrees Celsius, for about 90 seconds. Then adevelopment process and a hard baking process are performed on thephotoresist 317 to form a patterned mask layer 317 having a plurality ofholes 321. Each hole 321 exposes each corresponding insulation mound 315and a portion of each second conductive pattern 307. As the bakingprocess 319 is applied to the bottom of the substrate 301 prior to thedevelopment process, each hole 321 of the patterned mask layer 317 mayinclude an opening structure that shrinks from bottom to top and a tiltsidewall 323, as shown in FIG. 4. In the embodiment of the presentdisclosure, the angle .theta. between the tile sidewall 323 and thesubstrate 301 is less than 90 degrees, preferably, 45degrees.ltoreq..theta.<90 degrees.

Referring to FIG. 5, a conductive film 325 is formed comprehensively onthe substrate 301. The conductive film 325 may include a variety oftransparent conductive materials, such as ITO or IZO, or a variety ofmetal materials, such as copper or aluminum. Especially, the step offorming the conductive film 325 in the embodiment of the presentdisclosure uses a non-isotropic deposition process, e.g. a sputteringprocess or an evaporation process. Accordingly, as the holes 321 have a“top-small, bottom-large” structure, when the conductive film 325 isdeposited on the substrate 301 in a non-isotropic manner, the conductivefilm 325 (whether made of ITO or metal) only covers the surface of thepatterned mask layer 317, each insulation mound 315 in each hole 321,and a portion of each second conductive pattern 307. Besides, theconductive film 325 is not formed on the tile sidewall 323 of the hole321 by the shielding of the patterned mask layer 317. As shown in FIG.5, the conductive film 325(327) is formed along the curvature of theinsulation mound 315 and the conductive film 325 connects two adjacentsecond conductive patterns 307 a, 307 b electrically.

Please refer to FIG. 6. The patterned mask layer 317 is removed, forexample, by using an appropriate cleaning solution. As the tile sidewall323 of the holes 321 is not covered by the conductive film 325, aportion of the patterned mask layer 317 is thus exposed to the externalenvironment. Therefore, the cleaning solution can contact the patternedmask layer 317 and remove it, as well as the conductive film 325covering the patterned mask layer 317. But the conductive film 325 onthe insulation mound 315 is not removed. In this way, two adjacentsecond conductive patterns 307 a, 307 b in the same group (column) areelectrically connected by the conductive film 325 disposed therebetween,and the conductive film 325 atop the insulation mound 315 becomes abridge component 327.

With the above steps, a plurality of groups (rows) of the firstconductive patterns 303 and a plurality of groups (columns) of thesecond conductive patterns 307 arranged in different directions can beformed on the same side of the substrate 301, as shown in FIG. 7. Thefirst conductive patterns 303 in the same group (row) are connected bythe connection components 305 and extend along the first direction 309,while the second conductive patterns 305 in the same group (column) areconnected by the bridge components 327 and extend along the seconddirection 311. Each bridge component 327 straddles each insulation mound315, so the insulation between the first conductive patterns 303 and thesecond conductive patterns 307 can be maintained. Accordingly, thelayout formed by the first conductive patterns 303 and the secondconductive patterns 307 on one surface of the substrate 301 can serve asthe sensor electrodes of the capacitive touch screen, which can detectthe touch position by measuring the axis degrees along the firstdirection 309 and the second direction 309.

In addition, if the bridge component 327 is made of metal, due todifferences in etching selectivity, the metal manufacturing process ofthe bridge component 327 does not affect the first conductive patterns303, the second conductive patterns 307, and the connection components305 which are made by ITO. So, a conventional metal patterning processcan be carried out directly to replace the step in FIG. 4 and FIG. 5.For example, after forming the insulation mound 315 as shown in FIG. 3,a metal layer 329 referring to FIG. 8 is formed comprehensively on thesubstrate 301 and then patterned to form each of the bridge components327 as shown in FIG. 6. Because the size of the bridge component 327disposed between the second conductive patterns 307 a, 307 b is small,the light transmittance may not be affected. On the other hand, themetal with low resistance can compensate for the interface effectsbetween the second conductive patterns 307 a, 307 b and the bridgecomponents 327, thereby obtaining a better electrical connection rate.

In the second embodiment of the present disclosure, the first conductivepattern and the connection component can be formed first, the insulationmound is formed next, and the second conductive pattern and the bridgecomponent are formed last. Please refer to FIG. 9 to FIG. 11,illustrating schematic diagrams of the second embodiment of the methodof fabricating the capacitive touch panel in the present disclosure. Asshown in FIG. 9, a substrate 401 is provided at first. Then, a pluralityof groups of first conductive patterns 403 arranged in the firstdirection 409 and a plurality of connection components 405 are formed onthe substrate 401. Each first conductive pattern 403 is connected toanother adjacent first conductive pattern 403 in the same group by eachconnection component 405. The first conductive patterns 403 and theconnection components 405 can be formed simultaneously and aremonolithic. The first conductive patterns 403 and the connectioncomponents 405 include a variety of transparent materials such as ITO,which is fabricated by the similar process as that shown above and isnot described again.

Subsequently, a plurality of curved insulation mounds 415 is formed.Each insulation mound 415 covers at least a portion of each connectioncomponent 405. The fabricating method of the insulation mound 415 issimilar as shown above and is not described again.

Then, a plurality of groups of second conductive patterns 407 and aplurality of bridge components 427 are formed on the substrate 401. Theformation of the second conductive patterns 407 and the bridgecomponents 427 can use the aforementioned lift-off photoresist, as shownin FIG. 4 to FIG. 6. The only difference is that the exposed scope ofthe holes 321 may enlarge from the original bridge components 327 to thesecond conductive patterns 407 and the bridge components 427. Thedetails are the same and will not be described again. In another way,please refer to FIG. 10, which shows an enlarged schematic diagram ofthe circle C in FIG. 9. The left part L is the schematic diagram showingthe mask pattern 414 (described below) in the circle C, and the rightpart R is the 3D schematic diagram of the circle C. First, a transparentconductive film (not shown) is formed on the substrate 401comprehensively, followed by a deposition process to form a photoresistlayer (not shown) thereon. Then, a PEP process is provided by using themask pattern 414 as shown in the left part L in FIG. 10. The maskpattern 414 includes four regions. Region 4141 corresponds to the firstconductive pattern 403. Region 4142 corresponds to connection component405. Region 4143 corresponds to the second conductive pattern 407.Region 4144 corresponds to the bridge component 427. Region 4142corresponds to each already-formed connection component 405 that iscovered by each insulation mound 415. However, region 4142 slightlyprotrudes into the region of the insulation mound 415 (the insulationmound 415 is shown as the block D by a dotted line). Therefore, afterthe PEP process, the conductive film becomes the second conductivepattern 407, the bridge component 427, an auxiliary first conductivepattern 404 and an auxiliary connection component 406, and the secondconductive pattern 407, the bridge component 427, the auxiliary firstconductive pattern 404, and the auxiliary connection component 406correspond to the regions 4143, 4144, 4141, and 4142 respectively, asshown in the right part R in FIG. 10. In particular, the auxiliary firstconductive pattern 404 is formed on the already existing firstconductive pattern 403 and the auxiliary connection component 406 isformed on the part of the connection component 405 that is uncovered bythe insulation mound 415, thereby forming a double-layer conductivestructure, as shown in FIG. 10. As the region 4142 of the mask pattern414 protrudes slightly into the insulation mound 415, the correspondingauxiliary connection component 406 is disposed not only on theconnection component 405 but also on a portion of the insulation mound415. The protruding structure ensures the electrical connection betweenthe auxiliary connection component 406 and the below connectioncomponent 405, thus preventing their breakage.

The second conductive patterns 407 and bridge components 427 can also beformed in two separate steps. For instance, when the bridge components427 are made by metal, the above-mentioned two ways to form the secondconductive patterns 407 can be used. Then a metal manufacturing processis carried out to form the bridge components 427. The metalmanufacturing process is similar with the embodiment shown in FIG. 8,which will not be described again.

Please refer to FIG. 11. By using the above method, the secondconductive patterns 407 and bridge components 427 can be formed on thesubstrate 401. Each group of the second conductive patterns 407 isinterlaced with and insulated from each group of the first conductivepatterns 403. Each bridge component 427 is formed on each insulationmound 415, allowing the second conductive patterns 407 to be connectedto another adjacent second conductive pattern 407 in the same groupthrough the bridge component 427.

The method in this embodiment can also form a double ITO layer along thefirst direction 409 and along the second direction 411. When using thephoto-etching process to form the first conductive pattern 403 and theconnection component 405, the plurality of auxiliary second conductivepatterns (not shown) can also be formed along the second direction 411.Then, the insulation mound is formed thereon, which is fabricated by thesame method described. Then, the mask pattern 414 as shown in the leftpart L in FIG. 10 may be used to form the second conductive patterns407, the auxiliary first conductive patterns 404 and the auxiliaryconnection components 406.

In this embodiment of the present disclosure, the first direction 409and the second direction 411 are perpendicular. However, the arrangementcan be ordered to change the distribution of the conductive patterns, sothe first direction 409 and the second direction 411 intersect at thenon-perpendicular angle. In another embodiment, the substrate 401 can berotated in a counter-clockwise manner or in a clockwise manner, forexample, to make each group of the first conductive patterns 403 bearranged along the second direction 411, and each group of the secondconductive patterns 407 be arranged along the first direction 409. Themethod in the present embodiment further includes forming a plurality ofwires 408 and at least an alignment mark 410. For example, the wires 408and the alignment mark 410 can be formed by a metal manufacturingprocess before the formation of the first conductive patterns 403 andthe connection components 405. The step may also be placed between othersteps when not affecting the processes.

In the third embodiment of the present disclosure, the bridge componentscan be formed first, the insulation mounds next, and the firstconductive patterns, the second conductive patterns, and the connectioncomponents formed simultaneously last. Please refer to FIG. 12 to FIG.14, illustrating the schematic diagrams of the third embodiment of themethod of fabricating a capacitive touch panel in the presentdisclosure. FIG. 12 and FIG. 13 include a left part L and a right partR, and the right part R is the cross sectional diagram along line EE′ ofthe left part. Please refer to FIG. 12 first. A plurality of bridgecomponents 527 are formed on a substrate 501. Then a plurality of curvedinsulation mounds 515 are formed on the substrate 501, each of whichcovers each corresponding bridge component 527 and exposes both ends ofeach bridge component 527. The bridge components 527 may includetransparent conductive material or metal, which may be formed by aconventional exposure process or development process. The insulationmounds 515 are fabricated by the similar process mentioned above, whichwill not be described again.

Please refer to FIG. 13. A transparent conductive layer (not shown) isformed on the substrate 501 and patterned to form a plurality of groupsof first conductive patterns 503, a plurality of groups of secondconductive patterns 507, and a plurality of connection components 505.The arrangement and position of each component is the same as thedescription in FIG. 7. Each first conductive pattern 503 is connected toanother adjacent first conductive pattern 503 in the same group (row) byeach connection component 505 and each group of the second conductivepatterns 507 is interlaced with and insulated from each group of thefirst conductive patterns 503. As the bridge components 527 have beenformed on the surface of the substrate 501, two adjacent secondconductive patterns 507 c, 507 d can be electrically connected to eachother by the bridge component 527 below the insulation mound 527. Asshown in FIG. 14, the first conductive patterns 503 in the same groupare connected by the connection components 505 and extend along thefirst direction 509; the second conductive patterns 507 in the samegroup are connected by the bridge components 527 buried below theinsulation mound 515 and extend along the second direction 511, formingthe sensor electrode array to provide an excellent touch panelstructure.

Similarly, the first direction 509 and the second direction 511 in thisembodiment are perpendicular. The arrangement can also be ordered tochange the distribution of the conductive patterns, so the firstdirection 509 and the second direction 511 intersect at anon-perpendicular angle. The substrate 501 can be rotated in acounter-clockwise manner or in a clockwise manner, for example, to makeeach group of the first conductive pattern 503 be arranged along thesecond direction 511, and each group of the second conductive pattern507 be arranged along the first direction 509. The method in the presentembodiment further includes forming a plurality of wires 508 and atleast an alignment mark 510 on edge of the substrate 501. If the bridgecomponent 527 is made by metal, the wire 508 and the alignment mark 510can be formed on edge of the substrate 501 simultaneously when formingthe bridge component 527 in the beginning, saving one step and providingmore position calibration. The step may also be placed between othersteps when not affecting the processes.

Accordingly, the capacitive touch panel fabricated by the thirdembodiment, as shown in FIG. 13 and FIG. 14, includes a substrate 501, aplurality of groups of first conductive patterns 503, a plurality ofgroups of second conductive patterns 507, a plurality of connectioncomponents 505, a plurality of bridge components 527, and a plurality ofinsulation mounds 515, all of which are disposed on the same side of thesubstrate 501. Each insulation mound 515 covers each bridge component527 and exposes a portion of each bridge component 527. The connectioncomponent 505 straddles the insulation mound 515. The insulation mound515 is not limited to the curved shape formed by the aforementionedprocess, but may be an insulation protrusion in any shape. Each group ofthe first conductive patterns 503 is arranged along a first direction509 and each group of the second conductive patterns 507 is arrangedalong a second direction 511. The first conductive pattern 503 iselectrically connected to another adjacent first conductive pattern 503in the same group by the connection component 505 therebetween, and thesecond conductive pattern 507 is electrically connected to anotheradjacent second conductive pattern 507 in the same group by the bridgecomponent 527 buried below the insulation mound 515 therebetween.

In light of the above, the embodiments of the present disclosure providea method of fabricating a capacitive touch panel with fewer layers andhigher light transmittance. The capacitive touch panel includes a novelbridge structure which can reduce the thickness and the number ofstacking layers, thereby solving the conventional problems of low lighttransmittance and complicated fabrication process.

In addition, as the insulation mound used in the embodiments of thepresent disclosure includes a curved structure, the connection componentor the bridge component can be formed along the surface of the curvedstructure, forming an arc-shaped bridge structure. In this way, theruptured or poor contact phenomenon resulting from the conventionalbridge structure formed at a vertical or sharp corner surface can beavoided, greatly improving product yields as well as its lifespan.

In addition, the embodiments of the disclosure provide a variety offabrication methods for the bridge component by consideringcompatibility between the materials of the first conductive pattern, thesecond conductive pattern, the connection component, and the bridgecomponent, and are applicable to a variety of materials of the bridgecomponent. When the first conductive pattern, the second conductivepattern, and the connection component are made of transparent conductivematerial such as ITO, and the bridge component is made by ITO as well,because the patterning process can not use the same etching solution,the first embodiment in the present disclosure therefore provides afabricating method of forming the bridge component, as shown in FIG. 4and FIG. 5. The method includes forming a hole with a tilt sidewall, sothat during evaporation of the conductive film, the tilt sidewall is notcovered by the conductive film. The patterned mask layer and the aboveconductive film can be removed and the bridge component can be formedwhen not affecting the first conductive pattern, the second conductivepattern, and the connection component under the patterned mask layer.

If the bridge component is made of metal, in addition to theabove-mentioned method provided by the first embodiment, the disclosurefurther provides the third embodiment. As the metal and ITO layer havean etching selectivity, when the first conductive pattern, the secondconductive pattern, and the connection component are made of ITO, andthe second conductive pattern is made of metal, the bridge component canbe directly formed by a metal manufacturing process, which does notaffect the formation of the first conductive pattern, the secondconductive pattern, and the connection component. It is known that theelectrical conductivity of metal is much greater than that of ITO, so byusing the metal as the bridge component, the resistance of the touchpanel can be lowered and the sensitivity of the touch panel can beimproved.

Based on the above advantages, the embodiments of the present disclosureprovide a simple method of fabricating that uses only a few stackinglayers and exhibits high light transmittance. A variety of manufacturingprocesses are also considered to ensure the applicability to anymaterial of the bridge component. A good curved structure is alsoprovided to ensure the integrity of the bridge structure and provideexcellent utility for the process.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the disclosure.

What is claimed is:
 1. A method of fabricating a touch panel,comprising: providing a substrate; forming a plurality of bridgecomponents on the substrate; forming a plurality of insulation mounds onthe substrate, wherein each insulation mound covers each bridgecomponent and exposes a portion of each bridge component; and forming aplurality of groups of first conductive patterns arrange in a firstdirection, a plurality of groups of second conductive patterns arrangedin a second direction, and a plurality of connection components on thesubstrate, wherein each first conductive pattern is electricallyconnected to another adjacent first conductive pattern in the same groupby each connection component, each group of the second conductivepatterns is interlaced with and insulated from each group of the firstconductive pattern, and each second conductive pattern is electricallyconnected to another adjacent second conductive pattern in the samegroup by each bridge component below each insulation mound.
 2. Themethod of claim 1, wherein the first conductive patterns and theconnection components in the same group are formed simultaneously. 3.The method of claim 1, wherein the step of forming the insulation moundscomprises: forming a photoresist layer; performing a lithography processon the photoresist layer to form a plurality of photoresist patterns,wherein each photoresist pattern covers each bridge component; andperforming a baking process to make each photoresist pattern become eachinsulation mound.
 4. The method of claim 3, wherein the temperature ofthe baking process is between 200 to 300 degrees Celsius.
 5. The methodof claim 1, wherein the step of forming the insulation mounds comprises:forming an insulation layer on the substrate; etching the insulationlayer to form a plurality of insulation patterns, wherein eachinsulation pattern covers each bridge component; and providing a thermalreflow process to make each insulation pattern become each insulationmound.
 6. The method of claim 1, wherein the first conductive patterns,the second conductive patterns, and the connection components comprisetransparent conductive material.
 7. The method of claim 1, wherein thebridge component includes metal or transparent conductive material. 8.The method of claim 1, further comprising forming a plurality of wireson the edge of the substrate, wherein one side of each wire connects toone group of the first conductive patterns or one group of the secondconductive patterns and the other side of each wire stretches to theedge of the substrate.
 9. The method of claim 8, wherein the step offorming the wires further comprises forming at least an alignment markon the edge of the substrate.
 10. The method of claim 1, wherein anangle is between the first direction and the second direction.